I hear you on this and am surprised it has to be told to people, honestly. One of my biggest reservations about this particular friend was that there is NO WAY this would be a good situation for her. My partner for some reason is convinced that he is some kind of sex god who will enlighten her and help her discover her sexuality.

In terms of the limits, I know my list was ambiguous, I don't think it really makes sense to come up with a list a priori. It seems to me these decisions have to be made on a case by case basis, you know?

I was using categories as an example. You should discuss everything. Leaving stuff to chance is silly.

Things that must be discussed on a case-by-case go in "soft limits" category. Things that will always be no go in hard limit category. You will never be alright if he wants to date your mom. Hard limit. You will never be alright if he wants to date your sister. Or your best friend. Those are hard limits. So spell them out. Don't be ambiguous, or you leave room for him to go "you didn't say no until we discussed it just now and you're being unfair".

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"Regret for the things we did can be tempered by time; it is the regret for the things we did not do that is inconsolable." - Sydney Smith

Kyle: 27 year old male
Katie (rymmare): 25 year old female
Kids: girl: 5 years old, boy: 3 years old